Render scales

[cbenz]

Connected to #73 Fixes #74

The fix of #74 is needed for this PR, it is not a "two-features" PR ;-)

[cbenz]

@fpagnoux @MattiSG I'm not sure about the best way to test this PR with Watai. I'm open to propositions.

[fpagnoux]

Displays:

[fpagnoux]

I find it difficult to distinguish the different groups.

Suggestion: make the bottom border thicker and darker like this:

[fpagnoux]

I'm not sure about the best way to test this PR with Watai

What is the difficulty you are encountering ? Testing the table ?

[cbenz]

@fpagnoux I'd like to have some suggestions about which new Watai test to write.

[fpagnoux]

🚨 FORCE PUSH DETECTED DURING REWIEW🚨 👮 🚔

[cbenz]

New rendering after my new commit:

[benjello]

I don't know if it is the right place to make the following remarks but I put the here anyway:

• brackets should be displayed as follows: Entre 0 et 9700 €
• Rate should represented as percentage values i.e 5,5 %

[fpagnoux]

Some afterthoughts:

• Like @benjello, Entre 0.0 et 9700.0 seems clearer to me than Au dessus de 0.0. While À partir du is clear and simple for date ranges, I'm not sure it's limpid for marginal tax brackets (which are often misunderstood by many people).
• I'd also consider adding a header line to explicit what these values are .

Date	Tranche	Taux marginal

[fpagnoux]

About testing, following the spirit of the current tests, I'd have the following scenario :

• Go to the /impot_revenu.bareme page
• Check the headers (if we choose to add them)
• For the first two date blocks
  • Check that the date cell has a row span, and is properly formatted
  • Check that the first two thresholds are properly formatted
  • Check that the first two values are properly formatted.

If there is in france a case of a marginal scale that doesn't exist anymore (@benjello ?) , I'd also test its first line.

I would not test the values of the row span, rates and threshold, as this would make our tests break at any parameter update. This is a hole in our test net, but the maintenance cost is too high (except if one day we decide to run the tests on a dummy country).

[fpagnoux]

• Rate should represented as percentage values i.e 5,5 %

So far, we are not handling units in the new version of the API and therefore in the legislation explorer. This may come later.

[cbenz]

So far, we are not handling units in the new version of the API and therefore in the legislation explorer.

@fpagnoux But if you suggest adding a header with "Taux marginaux", why not adding a % unit?

[cbenz]

@fpagnoux @benjello Is this rendering OK for you (I took it from a random website)?

For the first bracket, if we say Entre 0.0 et 9700.0, I think 9700 is included.

But for the following brackets, would it be Entre 9701 et 26791?

Is it worth doing the + 1 operation?

---

Given this data from the API:

{
    "0.0": 0.0,
    "9700.0": 0.14,
    "26791.0": 0.3,
    "71826.0": 0.41,
    "152108.0": 0.45
}

• the first key (0.0) is a starting value of the first bracket
• the following keys (9700.0, [...], 152108.0) are stop values of the previous bracket

I didn't see it explained explicitly in https://github.com/openfisca/openfisca-web-api/issues/107 so I wanted to make it clear.

[cbenz]

My last commit renders like that:

Is is OK?

[fpagnoux]

I would not add the +1, I find it misleading.

Conceptually you pay 0% for what is under 9700 and 14% for what is above 9700.

9701 only plays a role because the income to tax happens to be rounded before applying the scale. Without rounding, which may be the case for some scales, it doesn't make sense: with 9700.5, I'm already in the 2nd bracket.

Also, when I read Entre 9701 et..., I understand that my 9701th euro won't be taxed, which is not the case.

[fpagnoux]

So far, we are not handling units in the new version of the API and therefore in the legislation >explorer.

@fpagnoux But if you suggest adding a header with "Taux marginaux", why not adding a % unit?

You're right. As we are in the case of a marginal scale, we know the unit is percent, so 👍 for me.